DIAGNOSTIC NEUROACTIVATION PET STUDIES

0.2%-1%的人口患有癫痫。大约四分之一 的癫痫患者难于接受药物治疗，大多数患者患有颞叶癫痫 脑叶癫痫。这些患者是颞叶切除术的候选对象。 不幸的是，手术后，许多人失去了命名能力。这 是一个例子，如果PET激活研究的敏感性是 改进，以便对单个个体的显著结果可以 如果能做到这一点，对病人的管理可能会得到改善。这样做的目的是 该项目是增强PET激活成像，直到这成为可能。至 日期，PET活化研究已经用于形成关于以下方面的结论 一群群病人。这项工作旨在加强活化研究，以便 在个别患者身上可以得出有意义的结论。 这项工作是对PET激活的五个方面的调查 技术。首先，并排测试比较(15-0)水和(15-0)水 0)丁醇。(15-O)丁醇已被提出(但不是 有效)作为潜在的更好的放射性示踪剂，因为它更自由 可以通过血脑屏障扩散。第二个领域是 对采集协议进行优化，以最大限度地提高 宠物研究。在该子项目中，任务开始之间的相对时间 以及数据采集、采集持续时间和任务 将对演示文稿进行调查。其中包括对 习惯化的影响。对抗性命名刺激任务将是 使用，但我们的意图是制定一套通用原则 优化任何激活任务。第三，识别的客观方法 大脑的激活区域将被开发出来。新技术的创新 建议的工作是直接操作原始数据(2D或3D 正弦图形)，其中统计属性是已知的，以产生图像 在每个像素(Z-图像)中具有相等的方差。从Z图像中， 大脑的任何特定区域被激活的概率可以 将被获得。在可接受的假阳性率下，所有这些都显著 激活区域是客观确定的。第四，最近的PET扫描仪 发展提供了收集3D数据的能力。使用3D数据 采集时，去除平面间隔膜以增加(增加一个数量级 量级)扫描仪的总体灵敏度，但增加的不是 在成像视场中均匀分布。此外，图像对比度为 由于散射分数大大增加而减少的。Z-Image 这些方法将用于2D和3D PET数据的并列测试 确定收购双方的相对优势。 我们预计，每一项的累积改善 子项目将产生一种PET激活技术，能够提供 关于个别患者的重要结论。这项工作是一项 原则性项目证明。这里开发的技术，特别是为 研究癫痫，同样适用于转移其他PET 对临床环境的激活研究。我们的长期目标是 开发一系列诊断激活测试，使医生能够 根据疾病的神经生物学来治疗神经疾病 而不是仅仅依靠出现的症状。

Between 0.2-1% of the population is epileptic. Approximately one quarter of epileptics are refractory to medical treatment and most have temporal lobe epilepsy. These patients are candidates for temporal lobectomy. Unfortunately, after surgery, many suffer a loss in naming ability. This is one example where if the sensitivity of a PET activation study were improved so that significant results for a single individual could be attained, management of the patient might be improved. The purpose of this project is to enhance PET activation imaging until this is possible. To date, PET activation studies have been used to form conclusions concerning groups of patients. This work intends to enhance activation studies so that significant conclusions can be drawn on individual patients. This work is an investigation into five areas of the PET activation technique. First, side-by-side tests comparing (15-0)water and (15- 0)butanol will be performed. (15-O)Butanol has been proposed (but not validated) as a potentially superior radiotracer because it is more freely diffusible across the blood brain barrier. The second area is an optimization of the acquisition protocol to maximize the information in a PET study. In this subproject, the relative timing between the task onset and the data acquisition, the duration of the acquisition, and the task presentation will be investigated. Included is an investigation into the effects of habituation. The confrontational naming stimulus task will be used but our intention is to produce a set of general principles for optimizing any activation task. Third, an objective method for identifying activated regions of the brain will be developed. The innovation in the proposed work is to directly manipulate the primary data (2D or 3D sinograms), where the statistical properties are known, to produce images with equal variance in every pixel (Z-images). From the Z-images, the probability that any particular region of the brain has been activated can be obtained. Given an acceptable false positive rate, all significantly activated regions are determined objectively. Fourth, recent PET scanner developments have provided the ability to collect 3D data. With 3D data acquisition, the interplane septa are removed to increase (by an order of magnitude) the overall sensitivity of the scanner but the increase is not uniform across the imaging field of view. Also, the image contrast is reduced because of a greatly increased scatter fraction. The Z-image methods will be used in side-by-side tests of 2D versus 3D PET data acquisition to determine the relative advantages of each. We anticipate that the cumulative improvement from each of these subprojects will produce a PET activation technique that is able to provide significant conclusions concerning individual patients. This work is a proof of principle project. The techniques developed here, specifically for studying epilepsy, are equally applicable to transferring other PET activation research to the clinical setting. Our long term goals are to develop a range of diagnostic activation tests that will allow a physician to treat neuro illnesses based on the neurobiology of their disease rather than relying solely on the presenting symptoms.